Thoughts on nnew facilities for score layout

In various other threads there has been discussion of how all the various General Style and Layout settings affect the score. Now that I've sorted through it for myself, I'm pretty good at getting what I want, and indeed wouldn't want to give up any of those controls. But it occurs to me there are a couple of common use cases for which a simpler interface would be very nice. Here are some of my ideas on that subject.

Page layout
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Right now, there are a number of settings that affect this: page size, scaling, margins, staff space, system spac page fill threshold, and others if your score involves lyrics or vertical frames. I suggest that while indend control of these is great, in many case, there is really only one thing foremost in my mind: the number of staves or systems I can fit on a page. So I propose a dialog that makes this first and foremost. Page size and margins might be controllable from this dialog as well, but I usually think of these as fixed. Imstead, I mostly play with scaling and with either staff or system space. For lead sheets and parts for a single instrument, it is mostly the system space I play with, since here is only one staff per system but many systems per page. For larger scores, it is mostly staff space I play with, since there is often only one system per page, but each system contains many staves. Either way, though, I am thinking mostly in terms of fitting more or fewer "lines" of music on the page.

So my proposed dialog would have a single main setting: lines per page. Increasing it would have the effect of reducing the scaling and/or the staff/system space to achieve the desired number of lines per page. There could furthermore be two sliders. The first and more important would be one that controlled the relative amount of scaling changes versus space changes. Dragging it one way would increase the size of the staves with a corresponding decrease in the spacing to keep the desired numbers of lines per page, and dragging it the other way would do the opposite. The other slider would be relevant only for scores that had both multiple staves per sustem but also multiple systems per page, and it would similarly control the relative amount of staff space changesnversus system space changes to keep a constant number of lines per page. But that's it: a number of lines per page, and the two sliders. Maybe allow you to change margins from here, too, but I am ambivalent about that.

I think this could actually be implemented on top of the current architecture relatively easily, but in order to be most effective, we'd really want these to be controllable per page, so that different pages could have different scaling and space settings in order to fit different numbers of lones per page. If nothing else, this ends up being necessary in because some pages might have vertical frames or staff spacers might throw off the calculations, but also, you might just want to better control where the page turns are. Making all these settings be per page instead of per score is more of an architectural change, it seems.

If that happened, though, I could also see it tying in with the mechanism for specifying page breaks. If you are looking at the first system of a page and think, "I really wish this were on the previous page", there should be a command to push it to the previous page, which would automatically increase the number of lines per page of that previous page by the number of staves in this system and make it so. It could perhaps automatically pop up the dialog to allow you to play with the sliders, or maybe you'd rather let it just pick good defaults and require a separate step to bring up the dialog. Meanwhile, the page that originally contained the system would now jave rrom for more systems, or if it ended with a manual page break, it would see its "lines per page" decrease, with a similar automatic rearranging of things.

Conversely, looking at the last system of a page, a command to push it to the next page, with similar effects on the desitnation and source pages.

Line Layout
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Right now this is done with a combination of scale settings, stretch settings, and manual line breaks, plus of course page size and margin settings. But similarly to the case with page layout, all we really care about most of the time is controlling number of measures per page. Here, I suggest that a dialog is overkill. The system I described above for pushing a system to the previous or next page, and having MuseScore automatically adjust other parameters, is what should happen here. This much is basically just like Finale. You push a measure to the previous line, and stretch is automatically reduced on that previous line to accomodate it. On the line that orinally contained the measure, either room is created for more measures, or, if it ended with a manaul line break, the measures are simoly stretched to fit (this much already hapens already). And conversely for pushing a measure to the next system.

Interesting, since stretch is already defined per measure, no architectural changes would be required to implement this - just the UI changes.